1. Field of the Invention
The present invention relates to a printer provided with an auxiliary storage such as a hard disk and a data processing method of the printer.
The present application is based on Japanese Patent Application No. Hei. 11-62962, which is incorporated herein by reference.
2. Description of the Related Art
In a conventional type printer, print job data from a host computer is stored in a receive buffer, the data stored in the receive buffer is sequentially interpreted, image data for printing and output is generated and printing is executed. As print job data has only to be sequentially interpreted and printed as described above, a so-called local printer has only to have a memory enough to temporarily store data for one band or data for one page for example according to the format of a print engine.
However, recently, as the coloring and others of a printed document are accelerated as a computer, image processing technology and others develop, the quantity of print job data increases. Also, in the case of a network printing system in which plural host computers share a printer via a network such as a local area network (LAN), print job data from the plural host computers is required to be sequentially processed. If a memory mounted in a printer has capacity for only one page, a host computer which desires to print a document for a few hundred pages is required to continue to sequentially send print job data for a long time. The other many host computers connected via the network are required to wait for a long time.
Therefore, a printer provided with an auxiliary storage such as a hard disk inside the printer so that received data is stored in the hard disk so as to promptly store enormous print job data and release a host computer early is recently proposed.
As a printer in which the above auxiliary storage is built can store a large quantity of data, it can release a host computer early. However, in the auxiliary storage, as a head is moved to a predetermined position on a rotated record medium and data is read/written, reading/writing speed is slower than that in case a memory such as RAM is accessed. For example, even if speed at which data is received from a network is 1 to 2 MB/s. and the processing of an image data generator is 1 MB/s., the data transfer rate of a hard disk drive (HDD) is normally approximately 500 kB/s. and is slow.
Therefore, when print job data is transferred via an auxiliary storage, it takes time for writing the data to the auxiliary storage and time for reading the data from the auxiliary storage and printing processing speed is greatly retarded. If a high speed interface, a direct memory access (DMA) and others are adopted, the data transfer rate of the auxiliary storage is enhanced, however, the manufacturing cost is increased.